Reading assignment: Hashing

[Hookipa71]

SHA-256

The process of guessing the values of the algorithm is random.The random guess of the algorithm then needs to be combined (concatenated?) with a nonce (or input used once at a unique occasion) , hashed again then matched to the complexity of a block. If there is no match then try again. To match an algorithm at a specific time of difficulty is solving for a limit at infinity.

[Rishi_Remesh]

Reading assignment: Hashing

What is the hashing algorithm called used in Bitcoin?
The hashing algorithm used in Bitcoin is called SHA-256 (Secure Hash Algorithm - 256).

Why is this hashing algorithm really hard (almost impossible) to brute-force?
Using the understanding of the SHA-256 hash algorithm and applying the theory behind “The Birthday Problem Paradox” in order to brute force one would have to try 2^128 different combinations which is impossible in a persons lifetime and requires a lot of computational power if being done by a computer.

[Fabrice]

@Tordek

What is the hashing algorithm called used in Bitcoin?
AES-256

The hashing algorithm used in bitcoin is SHA 256
(Secure Hashing Algorithm)

AES (Advanced Encryption Standard) is a symmetric encryption standard.
SHA isn’t encryption, it’s a one-way hash function

[Fabrice]

@MoCrypto

Because the difficultly rate is raised and lower to insure that the system is working smoothly and also to ensure that the POW process continue and miners do not solve equations simultaneously and create orphaned blocks.

Here we just mean brute forcing a Sha 256 hash.
Guessing the input based on a hash. You need to keep guessing information and check if it matches the hash you want to brute force. It would take you a lot of time and energy to guess the input right

[Tordek]

Thanks i corrected it…

[Fabrice]

@agonzo12

It is a one way encryption algorithm that produces an output of constant length regardless of the input, making it pre-image resistant.

But because the output has a fixed length, it is still possible, but not feasible. You need to be extremely lucky and you need so much time and energy that it’s just not worth it

[Fabrice]

@Hookipa71

The process of guessing the values of the algorithm is random.The random guess of the algorithm then needs to be combined (concatenated?) with a nonce (or input used once at a unique occasion) , hashed again then matched to the complexity of a block. If there is no match then try again. To match an algorithm at a specific time of difficulty is solving for a limit at infinity.

Here we mean why it is almost impossible to brute force a Sha256 hash.
It takes an input of any size (there is technically a limit) to a scrambled output of a fixed length. You can’t mathematically calculate the input from a hash. So brute forcing it, is the only way to guess the input from a given output. It’s like trying to guess a pincode of trillions of characters. You just try all combinations.
So you keep guessing input, hash it and check if the hash is the same or not.
This is just not feasible and doesn’t worth the effort because it would take you forever

[JustinP]

1 - Bitcoin uses the SHA-256 algorithm

2 - Any tiny change to the input makes a massive change to the output. Brute forcing it would take too long to be plausible.

[SGB]

1. What is the hashing algorithm called used in Bitcoin? SHA-256
2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
   The hashing function is by design one way, with pre image resistance the brute force method would have no leading intelligence. With so many possible inputs it would take for ever to find a match

[Dominik]

1. SHA 256

2. Because there are endless amount of computational possibilities !

[Andre_Niederkofler]

1. SHA 256
2. Because the Input has High-min Entropy. It doesn’t matter how long the Input, the output will always be 256. One would have to guess random Inputs, hash them and compare them, this takes way to long to be of any use for a hacker.

[Hectorgato]

SHA-256: Secure Hashing Algorithm 256.
Its impervious to brute force because the amount of data is huge you would have to find the right input after several attempts which in turn would take too long.

[Howmoney.work]

1. SHA-256
2. Because there are so many possibilities it would take so long time it doesn’t matter

[XyzjynX]

[Jamie_Frame]

What is the hashing algorithm called used in Bitcoin?
SHA-256

Why is this hashing algorithm really hard (almost impossible) to brute-force?
It would take an extremely long time to methodically arrive at the correct hash and the probability of guessing correctly is very low - almost zero.

[zanjakobjez]

1. Bitcoin uses SHA-256 hashing algorithm.
2. The possibility to find the input based on the output is so difficult it’s impossible.

[SMDadli]

1. SHA-256

2. The use of mathematical functions that create Hash makes is very hard to find the correct input to get the desired output.

[Clinton]

1. SHA-256 (Secure Hashing Algorithym
2. The output is randomly created and cannot be reverse-engineered. Inputs must be calculated individually without a known starting point.

[jsd]

1. SHA-256
2. The probability of breaking by brute-force is very low due to large computation involved in the possible inputs to match the hash.

[Peter_C]

What is the hashing algorithm called used in Bitcoin?
SHA256

Why is this hashing algorithm really hard (almost impossible) to brute-force?
Pre-image resistance. The vast number of possibilities in a sha256 hash.